Henry c



(No Model.)

H. G. MIOHELL.

BOILER COVERING.

. Patented Aug. 6,1895.

UNITED STATES ATENT OFFICE.

HENRY o. MIOI-IELL, OF TORONTO, CANADA.

BOILER-COVERING.

SPECIFICATION forming part of Letters Patent No. 543,984, dated August 6, 1895. Application filed September 29,1894. Serial No. 524,499. (No model.) Patented in (lanada geptember 20,1894,N0.47,059.

To all whom it may concern.-

Be it known that 1, HENRY O- MICHELL, a: subject of the Queen of Great Britain, residing at Toronto, in the Province of Ontario, Dominion of Canada, have invented certain new and useful Improvements in Boiler-Cow erings, (for which I have obtained Letters Patent in the Dominion of Canada, dated September 20, 1894, No. 47,059,) of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to an improved nonconducting covering for boilers, steam-pipes,

and other similar devices intended 'for the protection, distribution, and application of heat; and the object of the invention is to provide an extremely simple, cheaply-manufactured, and easily-applied non-conducting covering, which will form an efficient means of preventing the radiation of heat from the structure covered; and it consists, essentially, of an external covering in the form of a fab ric composed of flake-mica arranged in indeterminate layers, so as to form an infinite number of dead-air spaces, and held together by a suitable envelope or binding, so as to make a cover of a determined thickness, which may be applied to the structure, as more particularly hereinafter explained.

It is a Well-known fact that mica has exceptionally good non-conducting property, and I have found that by placing the flakes of refuse mica left over from that out out of the mines together in web-form, not too tightly pressed together, an infinite number of dead -air spaces are formed which are of great utility in preventing the radiation of heat. I utilize refuse mica, and the envelope is also of inexpensive material, so that the covering is produced at a trifling cost.

I provide a flexible, porous, non-compressible, non-conductive covering in web form which age will not deteriorate and which will not become so compact after a time as not to properly perform its functions.

Other objects and advantages of the invention will hereinafter appear, and the novel features thereof will be specifically defined by the appended claims.

The invention is clearly illustrated in the accompanying drawings, which, with the letters ofreference marked thereon, form a part of this specification, and in which- Figure 1 is a perspective cross-section showing a portion of the outer shell of a boiler or pipe with my covering applied to the same. Fig. 2 is a similar view showinga modified form of covering. Fig. 3 is alike view of still another alternative form. Fig. 4 is an enlarged 'detail of a portion of my covering, showing the manner in which the mica is connected together in web-form, the air-spaces and thickness of the pieces or flakes of mica being greatly exaggerated.

Like letters of reference indicate like throughout the several views.

Referring now to the details of the drawings by letter, A designates the shell of the boiler or a steam-pipe or other structure about which it is desired to place the covering.

In carrying out my invention I take enough refuse mica B in pieces or fiakessuch as are left when the larger pieces are cut out of the mines, or such as are left when the mica is cut into pieces for stoves or the like-any refuse pieces, in fact, to form the web of the requisite thickness, and then sew the same by wire-stitching C, as shown in Fig. 1, so as to parts the portions of the web being at the point of juncturewith the abutting portion formed on a bevel, as indicated, so that the surface will be smooth and without any raised projection. The outer edge of the upper beveled portion is sewed to the thick end of the abutting portionthat is, the bevel thereof.

D is a canvas or analogous covering which is preferably used over the mica and wire stitching, (shown in Fig. 1,) and this cover is secured together at the point of juncture of the ends thereof, as by stitching a.

In Fig. 2 I have shown the web as incased upon both sides with wire netting or gauze E, thus forming an envelope within which the mica is held in web form of a determinate width by theholding-stitches b sewed through portions of the mica-web at intervals, as indicated in Fig. 2, the adjacent ends of the gauze or netting being united, as by stitches c.

In Fig. 3 the web is shown as of less thickness than in the other views, and interposed between it and the shell of the boiler or other structure A are ribs or blocks or strips F, preferably of any non-conducting materialsuch as mica-0r in some cases even metal or wood might serve efliciently. In this form the wire-netting envelope E is present, as is also the canvas or equivalent covering D, the latter being upon the outside of the web, as shown.

Fig. 4 illustrates the web upon a larger scale before the wire-netting envelope or the canvas has been applied. As will be seen from this view the mica-flakes overlapping each other form an indefinite number of dead-air spaces, thus combining with the flakes of mica, which of itself is one of the best non-conductors, the next best non-conductorviz., deadair spaces. These dead-air spaces are practically entirely separate and distinct, and consequently the utility of the invention is enhanced to the greatest possible extent.

It will also be observed that as the mica is but the refuse of the mines split or formed into flakes of slight thickness the covering can be manufactured very cheaply.

Modifications in details may be resorted to without departing from the spirit of the invention or sacrificing any of its advantages.

The covering is applicable to uses other than those above enumerated-ior instance, for cold-storage buildings, refrigerators and such like structures, insulators, as a fireproof lining for safes, vaults, and the like, and as a deadening-filling for walls, ceilings, or floors, or as a packing or linin What is claimed as new is 1. A non-intercommunicating interstitial non-compressible non-heat-conducting flexible covering in web form, substantially as described.

2. A non-heat-eondncting covering composed of flakes of mica arranged in a common plane forming innumerable hollow non-communicating interstices and retained in Web form by stitching or its equivalent maintaining said hollow interstices, substantially as set forth.

3. A nonheat-conducting covering composed of flakes of mica arranged in a common plane forming innumerable hollow non-communicating interstices, a layer of wire gauze on opposite sides and retained in web form by stitching or its equivalent holding the flakes against movement with relation to each other, and an outer covering of canvas or other suitable material, substantially as specified.

In testimony whereof I afiix my signature in presence of two witnesses.

HENRY (J. MICHELL. Witnesses:

EDWARD G. Goonwnr, HERBERT J. Goonn. 

